A technique is known, in which a user returns, by pressing a power saving button provided in an image forming apparatus, the image forming apparatus that is in a power conservation state to a normal power state. Furthermore, in recent years, an image forming apparatus has been proposed, which detects, using a human-body detection sensor, a person who has come close to the image forming apparatus even when a user does not press the power saving button, and which automatically returns from the power conservation state to the normal power state (See PTL 1).
In PTL 1, a technique is disclosed, in which an image forming apparatus is returned, using two human-body detection sensors having different detection ranges, from the power conservation state to the normal power state. In the image forming apparatus disclosed in PTL 1, when a person who has come close to the image forming apparatus has been detected by a first human-body detection sensor having a large detection range, a second human-body detection sensor whose detection range is smaller than that of the first human-body detection sensor is activated. Then, when the person has been detected by the activated second human-body detection sensor, the image forming apparatus returns from the power conservation state to the normal power state.
However, in the image forming apparatus using human-body detection sensors, which is disclosed in PTL 1 described above, there is a case in which the image forming apparatus is not able to automatically return from the power conservation state to the normal power state, depending on a position at which a user stands up with respect to the image forming apparatus. For example, in the case where the user exists at the blind spot of the second human-body detection sensor, it is impossible for the second human-body detection sensor to detect the user. Thus, it is impossible for the image forming apparatus to automatically return from the power conservation state to the normal power state.
In the case where the image forming apparatus does not automatically return from the power conservation state to the normal power state, the user presses the power saving button, thereby returning the image forming apparatus to the normal power state. However, for the user who is accustomed to using the image forming apparatus that automatically returns, using a human-body detection sensor, to the normal power state, an operation for manually returning the image forming apparatus to the normal power state is an operation that the user is not accustomed to performing. Therefore, in front of the image forming apparatus, the user is forced to perform a task for returning the image forming apparatus to the normal power state.